Shy Mask That Shuts Up When It Sees People

by Friedlc

58K28774

Intro: Shy Mask That Shuts Up When It Sees People

It's sad that we have to wear face masks due to Covid -19. It's not a very enjoyable experience, makes you hot, sweat, nervous and of course harder to breath. There are thirsty times when you are urging to remove the mask but scared to do so.

What if the face mask could open up when in a safe environment, with no people around. So you can cool down and drink. But to make it safe again, the mask should be able to shut off when anyone is approaching.

STEP 1: Start From a Prototype

Since this is a wearable project, I started mocking up a cardboard prototype, this is the fastest and cheapest solution for the correct dimensions, etc.

STEP 2: How It Works and Part List

The plan is to use an Arduino Nano that read signals from 3 PIR sensors, if any sensor triggers positive, then it shuts down the door by controlling the servo, and lights up LEDs to tell which sensor is triggered.

Some parts I used:

3D printer
I used this one: https://amzn.to/3cfC9X1

Arduino Nano:

https://amzn.to/3cfC9X1 (Amazon)

https://amzn.to/3cfC9X1 (Banggood)

PIR Sensor: HC SR 501 https://amzn.to/3cfC9X1 (Amazon)

Mini Servo: https://amzn.to/3cfC9X1 (Amazon)

https://amzn.to/3cfC9X1 (Banggood)

Wire sleeve: https://amzn.to/3cfC9X1 (Amazon)

Water decal paper for laser printer: https://amzn.to/3cfC9X1 (Amazon)

Protoboard https://amzn.to/3cfC9X1 (Amazon)

DISCLAIMER: This list contains affiliate links, which means that if you click on one of the product links, I’ll receive a small commission. This help support me and allows me to continue to make instructables like this. Thank you for the support!

STEP 3: How PIR Sensor Works and Why It's Not the Best Sensor for This Project

Under the lens of the HC-SR501 sensor, there are actually 2 sensors and a comparator circuitry. It sends out HIGH when the 2 sensor readings are different.

So if the sensor is stationary, the background will make 2 sensors with same reading, when a person or object with heat radiation walks by, one of the sensor will read the difference, thus trigger the module.

However, if you install the sensor on a moving platform, the constant motion will trigger the module often because environment, even though there is nobody come across. Pretty much everything have IR radiation.

Though it's not the exact sensor to detect human, it works for the mask application, even makes it safer since it always false positive to keep it shut.

STEP 4: Designing the Mask

To cover the full 360 degrees around you, I picked 3 sensors, 2 on the cheek, and one on the back of head. The sensor has a 110 degree range so that adds up to almost a full circle.

2 white ball(lens) on cheek will be quite funny looking like a clown, so I started some rough sketches, for a sci-fi look. With that style in mind and earlier dimensions from the mock up, we can start 3d modeling

STEP 5: 3D Modeling

I used fusion 360, starting form the major parts and mechanisms, then adding more details for the sci-fi look.

STEP 6: Putting All the Parts Together

STEP 7: Electronic Connections

The connection is quite simple, a lot of 5V, GND and digital pin connections. Since the Arduino Nano has very limited power ports, I created my own expansion using protoboard and some pins. Just solder all the wires together to make a rail.

I also made a lot of connectors(turned out not necessary and caused a lot of trouble), at a time I made a 4 pin connector that I have to figure out direction every time. Later I updated them using the Poka-Yoki philosophy, which is make all the parts coming together in an only possible way.

STEP 8: The Code

Very straight forward coding, basically a condition loop. When any sensor is triggered, it shuts down the door immediately and lights up corresponding LEDs.

See code attached:

STEP 9: Future Improvements

Check how it works in the video.

There are 2 disadvantages of this design.

1. The sensor false positive problem, a better sensor or even camera with AI would make it more accurate.

2. I didn't put in effort to seal the mask properly, but had thought of how to seal the door area. I think the fish mouth could be a very interesting mechanism to test out in the future.

This is not by any means a perfect project, but hope this could be your inspiration or entertainment.

Thanks for watching and see you next time!

DesignMaker

http://youtube.com/chenthedesignmaker

50 Comments

Seppywawa 3 years ago

You need to add a snot wiper! The moist heat created from closed exhalations causes post nasal drip. I do not wear maskes! I am project creator. I have worn masks (dust masks) that seem to be so popular post Covid-19. I wear a mask while sanding, dealing with dusty situations and for noxious fumes, a respirator. I take frequent breaks while performing these operations. In part, to wipe my mouth and nose of sweat and snot. Your project is novel in concept however, prolonged wearing of any face covering can cause more problems than the covering might prevent or solve! If you are fearful of this thing stay away from other people. A mask is not a solution for the public at large!

en2oh 3 years ago

Seppy: you don't know what you're talking about! :) (smiley for politeness)
I wear a mask all day. I'm also a medical doctor. If I have post nasal drip, by definition, it comes out the BACK of my nose, not the front! Sheesh. "post" op is "after the operation" "Pre" op is before.

As far as nasal congestion goes, the world is a different place when you work in a dust filled environment. This would not be an adequate solution - nor would anything but a mask designed for that purpose.

The reason I'm a bit cranky here is that the post seemed to take a swipe at masks in the context of public health and that is just plain wrong. Masks are not sufficient but are necessary to help address COVID spread. When coupled with physical distancing and ideally, with an effective vaccine.... the numbers go down and we begin to get back to normal! (BTW, the evidence does not support the idea that the current vaccine prevents infection in others. IT might prevent transmission, but we just don't know. What it does do for certain is reduce the severity of the disease you might catch)

Sorry for the tangent,.... :)

johndremmer 3 years ago

Hey everyone. I used almost all bits of this Instructable and on top of needing to make a video for me and my friends, I also made it with you all in mind. I ran into a lot of trouble along the way and I detailed what they are and my workarounds.

https://www.youtube.com/watch?v=EvM51oWq7xY

If you have any further questions, you may comment on them here, on the video, or email me at JohnDRemmer@gmail.com

gmartonic 3 years ago

keep going....fun to watch

johndremmer 3 years ago

God bless you, and I'll tell you why. I've gone so far that I've almost phased out this system from my mask, and in turn I forgot I even made that video. I think you sparked I desire to improve the reliability of my system now. As thanks, I'll show you pictures of what the mask looks like now.

rossemo 3 years ago

Did you print the struts shown in the first picture of step 6? Great job on the mask and the instructable!

mrsowlsclass 3 years ago

Hi! This video is great for a design thinking at-home project that I'm working on with some of my classes. I teach at a vocational school (ages 15+) for technical professions, and we are creating prototypes at home to practice technical English. Thanks for showing the prototyping process and how developing perfect products takes a lot of imperfect prototypes to get them to where they are ready for production! Also I think your mask is really cool looking as an art project :)

MidnightDave 3 years ago

I think you can address the false positive issues taking a tip from the alarm industry.
Like you illustrated with the basic PIR concept, you were "half right".
The PIR sensor is indeed actually 2 sensors side-by-side, and the idea is that "motion" in front of the compound "eye" lens, will cause a hot spot to move between the two targets... So what we are looking for is a transition pulse pattern between the targets right? And in theory, the static background heat will set the base bias level on both targets...
Works great until... yeah, you move the sensor because now the entire background becomes a rapid series of transitions across the two sensor elements. So basic false positive trigger isolation is done on the daughter board with the 1-2 switch, meaning how many LR or RL (vs LRLR or RLRL) target transitions are required to send a "triggered" output.
So first mitigation is pulse counting off of all of the sensors. And second is to take the outputs right from the sensor vs the daughter boards. (get the actual pulse behavior from the sensor)
Side benefit is that you are getting a cheap IR gyro element behavior. Think like the scroll wheel in a mouse, if ALL of your sensors are showing a pulse pattern RLRLRLRL from the sensor elements, then obviously your are rotating the whole unit. The trick at that point is setting tolerance in the code to evaluate the buffers to determine if indeed this is a global change.
The other trick might be to incorporate an actual gyro sensor to give an actual reference to the design on "dampening" response.
All in all, love the project! It reminds me of hardware projects for robotics in the 80's!

sanjayb48 3 years ago

Your presentation style is awesome! And now Batman has a new and worthy villain ;) Good job, dude.

Daeras 3 years ago

Nice idea, as for filters, why don't use a filter cartridge from an industrial respirator. Find a spot to attach it.

I think the sensor behind you is a good idea, but for the front, a manual trigger would probably work better and maybe an override for when you stick a straw in there.

What about small cameras with recognition software like they use with security cameras which track people.

Just some thoughts.

As an alternative idea, what about a vented mask, you use a filter cartridge and a little fan that keeps on venting the mask to keep you cool and to overcome the filter pressure drop.

snowf7 3 years ago

I am glad to see how creative people can be and what they can come up with in an emergency situation. Good job. Great post. The detailed instructions are wonderful.
I live in Canada and our Prime Minister recently did a public announcement telling us that we need not wear a mask unless we are infected. He said that it will not help to control the spread of the virus if healthy people wear masks. (Check the speaking "moistly" report) If anyone has heard differently in your country, please let me know. Thank-you.

e0142494 3 years ago

That's what happened to us in Singapore, at first they said only use it when you are sick, then they did a flip flop and now everyone has to wear a mask or we will be arrested...

snowf7 3 years ago

What I find to be really odd is that with such high numbers of people who (we have been told) have died of this virus, I have yet to talk to anyone here in Ontario who has lost a friend or family member. No one seems to know of anyone who has been touched by this personally, other than in the old age homes where the death rate is the same as for any other regular flu virus. Right now I am watching a Freedom March that took place yesterday in Vancouver, which is on our west coast. It is a very interesting time.

stumitch 3 years ago

My Family is in the healthcare profession... an ER Nurse and GP Doctor. Covid19 is real. People are dying and it is contagious. I considered the idea of a conspiracy at first but that was knocked down when I talked with my two Nieces in the hospital. Thanks for making the mask! The idea is very good and technically, I love the idea!

snowf7 3 years ago

I can't take credit for making the mask. It was made by Friedlc.

cndlaugh 3 years ago

There are still too many asymptomatic people to assume you are not "infected". If everyone assumes they aren't infected and doesn't wear a mask, more people are at risk. From what I have seen, there is a significant percent of the population walking around infected with no symptoms at all. That is why most areas are highly recommending, if not requiring, ALL people wear a face mask of some sort. Even a simple cotton mask does protect the "wearer" to a certain extent and it protects others if said "wearer" ends up being infected.

mgettles 3 years ago

Great design. Suggest adding a bypass button to temporarily interrupt closure for drinking or put a plug in port on the outside for straw and a permanent silicon tube on the inside. That would allow drinking regardless of door position.
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